The present invention relates to a shaft seal for the gap between a bore hole and a shaft guided therein and is composed of a contact pressure ring with elastic properties and a thin sleeve of polytetrafluoroethylene which is permanently joined to the inner wall of the ring.
A seal of a related type of design is known from Chemie-Ingenieur-Technik, Vol. 27, 1955, page 282, wherein is given the design of a stuffing gland packing for a centrifugal or plunger pump. The contact pressure elements are arranged axially one behind the other with a hat sleeve made from polytetrafluoroethylene and having radial projections serving as a spacer. As is well known, the material of the hat sleeve used has very little mechanical strength which makes it necessary to use a shaft with a high-grade surface. This requirement, however, is very difficult to achieve because of high manufacturing costs and the corrosive and abrasive effects which occur during continuous operation.